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RGMII TXCK quality get bad after SATA clk pll been initialized

Hi 

My customer meet the issue that RGMII fails to send out packages>300K in Kernel stage(while it is ok in uboot). 

They have made experiment to identify that when  static inline void ti814x_sata_pllcfg(void)  been excuted, the RGMII TXCK go bad, other signals looks fine.

Customer are using the SATA clk as 5MHz ref clk for RGMII.

-The 1st pic shows the waveform in uboot stage

-The 2nd pic shows the waveform in kernel stage

The PHY is realteck 8821E, it is connected 100M network.

Could you help on this?

What I have asked customer to try:

1.RGMII ref clk can be muxed to external 50MHz clk, i ask customer to use external clk to double check & confirm the SATA clk is the root reason.

2. use 10M, 1000M network to see if this issue is still there.

BR,

Eason